Frisian used to be the language that was considered the closest to English. Many scholars now consider Scots to be closer. But even though Frisian might have gone from near relation to kissing cousin, it still has strong connections to the English language.

Frisian is actually three very similar languages. North Frisian is spoken by about 10,000 people in Schleswig-Holstein in northwestern Germany. Sater Frisian is spoken by about 2000 people in Lower Saxony, next to Schleswig-Holstein. West Frisian is spoken by around 350,000 people in the province of Friesland in the Netherlands, and is usually called just Frisian.

English and Frisian are both Germanic languages. Here's a simplified family tree:

How much alike are English and Frisian? Here's a poem in both languages that shows how similar they can be:

Frisian: Bûter, brea, en griene tsiis is goed Ingelsk en goed Frysk.

English: Butter, bread, and green cheese is good English and good Fries.

The poem is pronounced about the same in either language. Here are some more examples:

Wat is dit? What is this?

Wat kostet dit? How much is this?

Wat is jo namme? What's your name?

Wêr komme jo wei? Where are you from?

Ik hear dy. I hear you.

Of course it gets harder after that:

Us Heit, dy't yn de himelen is

jins namme wurde hillige.

Jins keninkryk komme.

Jins wollen barre,

allyk yn 'e himel

sa ek op ierde.

Jou ús hjoed ús deistich brea.

En ferjou ús ús skulden,

allyk ek wy ferjouwe ús skuldners.

En lied ús net yn fersiking,

mar ferlos ús fan 'e kweade.

That's the Our Father in Frisian, and here it is in English:

Our Father, which art in Heaven

Hallowed be thy Name.

Thy Kingdom come.

Thy will be done,

in earth as it is in Heaven.

Give us this day our daily bread.

And forgive us our trespasses,

As we forgive them that trespass against us.

And lead us not into temptation;

But deliver us from evil.

Even though there are similarities, especially in grammar, English and Frisian speakers generally can't understand each other, which makes them separate languages.

Around the sixth century A.D. invaders from northwest Germany pushed their way into England. They spoke dialects of German that included Anglo-Saxon and Frisian and that were probably mutually understandable. As they settled into their new English home, they continued to speak a Germanic language that we call Old English.

The Frisian speakers among the invaders left a number of place names in England:

In Yorkshire Frisby, Frising hall, and Fryston

In Suffolk Fressingfeld, Friston, Framlingham, and Ipswich

In Lincoln Friston, Friesthorpe, Newark, and Boston

There are also variations of Friesland in Leicester, Nottingham, and Worcestershire, and many other examples.

In 1066 the Normans under William the Conqueror attacked and took over England. And, although the Normans and English weren't really interested in having a dialogue, they had to communicate just to get daily business done. So, over the next three centuries, the Norman French and Old English languages merged. Eventually they became Middle English, and then modern English. This set English (and also Scots) quite a bit apart from its German relatives because of the large influx of Latin words from Norman French. That accounts for a lot of the difference between the English and Frisian of today. Scholars generally consider Frisian closely related to Dutch.

Nowadays Frisian is a minority language, and is protected in the Netherlands. But it wasn't always that way. In the Middle Ages Frisian was spoken all along the North Sea's southern coast, and was an important language of trade in the Hanseatic League. The area occupied by Frisian speakers was called Frisia Magna, or Greater Frisia. But in 1498 Duke Albert of Saxony took over Friesland and changed the language of government from Frisian to Dutch. Things were never the same after that.

But Frisian is still alive and well, and its speakers are proud of their heritage. You can hear Frisian spoken and learn some Frisian here: http://www.allezhop.de/frysk/

You can also hear a song sung in Frisian here: www.talkpa.net/frisian-closest-language-english-t7133.html

Picture from Wikipedia Commons.  It shows a canal in Friesland.

Sources:

http://en.wikipedia.org/wiki/West_Frisian_language

http://andromeda.rutgers.edu/~jlynch/language.html

http://www.bigsiteofamazingfacts.com/what-is-the-closest-language-to-english frisian

http://www.talkpa.net/frisian-closest-language-english-t7133.html?s=c212e98f90fbee4e31d7531073d27fb2&

http://www.omniglot.com/writing/frisian.htm

 http://en.wikipedia.org/wiki/Frisian_languages

http://www.boudicca.de/frisian1.htm

http://web.cn.edu/kwheeler/IE_Centum_Frisian.html

http://www.antimoon.com/forum/t10603-15.htm f

Jessie M. Lyons, "Frisian Place-Names in England," PMLA Vol. 33 No. 4, 1918